Types of Grain Dryers and Their Importance in Farming

Grain — a living organism that reacts to external conditions. Humanity has long been cultivating grain crops and gradually seeks the best methods to reduce losses of harvested crops, i.e., their processing and subsequent storage. Long before the advent of technological grain drying equipment people experimented with simpler methods.

In the 19th century, these were floor dryers: a sort of spacious oven, on the surface of which grain was spread, and the drying process occurred through constant mixing.

Later, mesh grain dryers appeared. Grain was spread on mesh racks, beneath which a heat source was placed. But these devices required manual labor and were inefficient.

Conditions for Proper Drying

A crucial stage in processing the harvested crop is drying grains. The simplest method — but also the most impractical among existing ones — is to spread grain in a thin layer in a dry, ventilated room or on a sunny yard. Weather and climatic conditions do not favor proper drying of grain crops.

For preservation, the following is required:

• a clean and dry storage facility;
• grain crop must be cleaned and dried before storage.

Different crops require different ambient humidity levels. For example, wheat requires 15%, sorghum — 13–14%, etc. If humidity is noticeably higher, there is a high risk of losing the entire harvest. In a humid environment, bacteria multiply actively and release a significant amount of heat, which leads to a significant reduction in material quality.

Types of Grain Dryer Constructions

Currently, there is a wide selection. More economical and efficient machines are offered.
Dryers are classified by:

• air heating (divided into two operating modes — continuous and intermittent. In the first case, drying occurs at a steady state; in the second case, the moisture content of the grain material varies in each section of the dryer chamber, and this mode is suitable for small batches of grain homogeneous in quality);
• technological scheme (direct-flow and recirculating. In the first case, grain material passes through the chamber once; in the second case, the grain material is returned and mixed with a new batch);
• grain layer condition (gravity-driven, suspended layer, stationary).
  
  

The following types of dryer chamber constructions are distinguished in grain dryers:

• shaft-type (the most popular construction type, with a high moisture removal range, allowing processing of crops grown in Russia and CIS countries);
• drum-type (less effective than shaft dryers in moisture removal);
• column-type (assembled from modules and columns, productivity of these dryers depends on the number of sections);
• carousel-type (capable of processing crops with higher moisture content, but are too energy-intensive, which makes them inferior to shaft grain dryers);
• tower-type (requires frequent cleaning of screens, suitable for processing a limited number of grain crops).

Russian-made Grain Dryer Models

AO «Melinvest», a manufacturer of agricultural equipment, produces and supplies the following grain dryers:

• column-type grain dryer Astra. Suitable for producers specializing in cultivating large volumes of commercial wheat and corn (excluding oilseed crops). Productivity from 8 to 20 tons per hour.
• shaft-type grain dryer Vesta. Characterized by low noise and high environmental friendliness. Operates on various temperature regimes, suitable for processing a wide range of crops. The machine’s durability is based on high-tech processing of its components.
• Grain dryer Vesta ECO. An improved model belonging to the new generation of drying equipment. Drying mode adjustments — down to 0.5 degrees, low fuel consumption, and reduced noise level. Thanks to the "rest" function, both surface and endosperm of the grain material are dried. Productivity ranges from 20 to 50 tons per hour.

The company is located in Nizhny Novgorod, and equipment is delivered either by its own transport fleet or via transport companies with which contracts are signed. Specialists also perform installation of delivered equipment (which includes assembly, commissioning, putting into operation, and staff training).